Signalment, clinicopathological findings, management practices and comorbidities in cats with diabetes mellitus in Germany: cross-sectional study of 144 cases.

Abstract

OBJECTIVES: The aim of this study was to describe signalment, clinicopathological findings, management practices and the occurrence of comorbidities in feline diabetes mellitus (DM) in Germany. METHODS: This was a cross-sectional study using questionnaires and laboratory submissions to a commercial laboratory, Antech Lab Germany, between May 2021 and July 2022. Inclusion criteria were diagnosis of DM by the attending veterinarian and submission of a completed questionnaire besides blood samples. Laboratory testing included haematology, serum biochemistry, concentration of total thyroxine (TT4), insulin-like growth factor 1 (IGF-1), cobalamin (COB), fructosamine, b-hydroxybutyrate and DGGR (1,2--dilauryl--glycero-3-glutaric acid-[6'-methylresorufin] ester) lipase activity. Data are presented as the median (range) and analysed by non-parametric tests.&#x2009;<0.05 was considered statistically significant. RESULTS: The median (range) age of the 144 diabetic cats at diagnosis was 11 years (0.9-18.7), 66.4% were male, 84.6% were domestic shorthair, 50.4% were currently overweight and 61.5% were previously overweight (body condition score >5/9). Most cats were treated with insulin (84%), most commonly protamine zinc insulin (57.5%). Blood glucose curves or continuous glucose monitoring alone or in combination with other methods were performed to adjust insulin therapy in 70.6% of cats. Based on questionnaires, 78.6% were poorly controlled and 21.4% were well controlled. Increased TT4 occurred in 3/139 and hyperthyroidism was known in 5/139 cats (frequency of known/suspected hyperthyroidism: 5.8% [n&#x2009;=&#x2009;8/139]); 17.5% (n&#x2009;=&#x2009;17/97) had increased IGF-1 (IGF-1 >746&#x2009;ng/ml, cut-off for hypersomatotropism with the chemiluminescence assay used in this study); 24.5% (n&#x2009;=&#x2009;34/139) had COB <295.2&#x2009;pmol/l and 54.2% (n&#x2009;=&#x2009;78/144) had increased DGGR. Cats with IGF-1 >746&#x2009;ng/ml were receiving a higher insulin dose than cats with IGF-1 &#x2264;746&#x2009;ng/ml (median 1.63 vs 0.86&#x2009;U/kg/day,&#x2009;=&#x2009;0.018). CONCLUSION AND RELEVANCE: Increased DGGR and increased IGF-1 indicating hypersomatotropism are common in diabetic cats and should be tested for. Almost one-quarter of diabetic cats might require COB supplementation.